Reactive ion etching apparatus

Patent metadata

Field	Value
Publication number	US-10991591-B2
Application number	US-201816624414-A
Country	US
Kind code	B2
Filing date	Dec 6, 2018
Priority date	Jan 29, 2018
Publication date	Apr 27, 2021
Grant date	Apr 27, 2021

Abstract

The reactive ion etching apparatus of this invention has a stage provided with an electrostatic chuck having a pair of electrodes. At the time of etching a to-be-processed substrate, by applying DC voltage to the pair of electrodes, the to-be-processed substrate is electrostatically absorbed to the electrostatic chuck. In this reactive ion etching apparatus, a radio-frequency power source connected to the stage, through a first output line, applies bias potential to the to-be-processed substrate. The radio-frequency power source is also arranged to be connected through a second output line to the pair of electrodes so as to apply radio-frequency potential in a manner to be superposed on the DC voltage. The first capacitor and the second capacitor are respectively interposed in the first output line and the second output line. A capacitance ratio of the first capacitor to the second capacitor is set to a range of 2.5 to 25.

First claim

The invention claimed is:

1. A reactive ion etching apparatus comprising:
a stage on which a to-be-processed substrate is disposed inside a vacuum chamber;
a gas introduction means for introducing an etching gas into the vacuum chamber in vacuum atmosphere;
a plasma generation means for generating inside the vacuum chamber a plasma which ionizes the introduced etching gas;
a radio-frequency power source connected to the stage through a first output line so as to apply bias potential to the to-be-processed substrate;
the stage being provided with an electrostatic chuck having a pair of electrodes so that, at the time of etching the to-be-processed substrate, DC voltage is applied to the pair of electrodes, whereby the to-be-processed substrate is electrostatically absorbed to the electrostatic chuck;
wherein: the radio-frequency power source is arranged to be connected, through a second output line, to the pair of electrodes so as to apply thereto radio-frequency potential in a manner to be superposed on the DC voltage;
both a first capacitor and a second capacitor are interposed respectively in the first output line and the second output line; and
a capacitance ratio of the first capacitor to the second capacitor is set to a range of 2.5 to 25.

2. The reactive ion etching apparatus according to claim 1 , wherein at least one of the first capacitor and the second capacitor is a variable capacitor whose capacitance is variable.

Assignees

• Ulvac Inc

Inventors

• Kamimura Ryuichiro
• Osada Yamato

Classifications

• H10P72/722 Primary

  Details of electrostatic chucks · CPC title

• H10P50/242 Primary

  of Group IV materials · CPC title

• H01J37/32706

  Polarising the substrate · CPC title

• H01J37/32697

  Electrostatic control · CPC title

• H01J37/32577

  Electrical connecting means · CPC title